WSUS Client Side Targetting missing

[Chris_Wallace]

Hi,
I am trying to write a report which shows servers which are not members of one of our windows update security groups used to control client side targeting.
I have searched the community site and found similar reports for reporting on AD group membership and have written the following. Can anyone tell me what I am doing wrong? I have tried Not In and Not Exists. The query builder does not allow Not In and Not Exists returns no entries. The subquery I have tested separately and does bring back all servers in a group.

Select Distinct Top 1000000 tsysOS.Image As icon,
tblAssets.AssetID,
tblAssets.AssetName,
tblAssets.Domain,
tblAssets.IPAddress,
tblAssets.Firstseen,
tblAssets.Lastseen,
tblAssets.Lasttried,
tblADGroups.Name As ADGroupName,
tblADGroups.Description As ADGroupDescription,
tsysOS.OSname
From tblAssets
Inner Join tsysOS On tsysOS.OScode = tblAssets.OScode
Inner Join tblAssetCustom On tblAssets.AssetID = tblAssetCustom.AssetID
Inner Join tblComputersystem On tblAssets.AssetID = tblComputersystem.AssetID
Left Join tblADComputers On tblAssets.AssetID = tblADComputers.AssetID
Left Join tblADMembership On tblADMembership.ChildAdObjectID =
tblADComputers.ADObjectID
Left Join tblADGroups On tblADMembership.ParentAdObjectID =
tblADGroups.ADObjectID
Where tsysOS.OSname Like 'Win 2%' And Not Exists(Select Distinct Top 1000000
tblAssets.AssetName
From tblAssets Left Join tblADComputers On tblAssets.AssetID =
tblADComputers.AssetID Left Join tblADMembership On
tblADMembership.ChildAdObjectID = tblADComputers.ADObjectID Left Join
tblADGroups On tblADMembership.ParentAdObjectID = tblADGroups.ADObjectID
Where tblADGroups.Name Like '%sg-wu%')
Order By tblAssets.AssetName,
ADGroupName

Many Thanks in advance
Chris